Molded plastic string instrument



y 1, 1956 D. J. ROSENHEIM OLDED PLASTIC STRING INSTRUMENT 2 Sheets-Sheet 1 Filed Oct. 2 1950 INVENTOR Dew/dd asenhezim ATTRNEY y 1, 1956 D. J. ROSENHEIM 2,743,644

OLDED PLASTIC STRING INSTRUMENT Filed Oct. 2, 1950 2 Sheets-Sheet 2 INVENTOR Daw'a'J asen A RNEY United States Patent MOLDED PLASTIC STRING INSTRUMENT David J. Rosenheim, Deal, N. J., assignor to Lapin Products, Inc., Newark, N. J., a corporation of New York Application October 2, 1950, Serial No. 187,857 3 Claims. (Cl. 84-305) The present invention relates to a molded plastic string instrument, and it particularly relates to a molded plastic ukulele.

It is among the objects of the present invention to provide a molded plastic string instrument and particularly a molded plastic ukulele which will be durable, readily manufactured, give an attractive musicalsound and which may be readily played by a learner or beginner or by an amateur or professional string-instrument player.

Another object is to provide a molded plastic string instrument in which the parts will be so molded together as to give the desired sound effect and enable maintenance and adjustment of proper tension upon the strings without undue strain upon the instrument and without loss of tone over long periods of time and without varying atmospheric conditions affecting the same.

Still further objects and advantages will appear in the more detailed description set forth below, it being understood, however, that this more detailed description is given by way of illustration and explanation only and not by way of limitation, since various changes therein may be made by those skilled in the art without departing from the scope and spirit of the present invention.

In accomplishing the above objects, it has been found most satisfactory, according to one embodiment of the present invention, to form the back of the sound box, the neck and the tensioning adjustment plate of a one-piece, molded to the hollow shell plastic.

The top of the box, the neck and the adjustment board are all desirably formed of plate members suitably provided with interlocking grooves to be positioned upon and to closely fit upon the edges of the one-piece body.

Desirably, these cover plates are adhesively connected to the shell by an adhesive solution, which will soften both the shell as well as the cover plate.

The lower support and holder for the strings, which may be of nylon, gut or other suitable material, is also desirably adhesively attached to the lower part of the cover for the main box of the instrument.

A principal feature of the present invention resides in the manner of holding the adjustment pins by which the tension on the nylon or gut strings may be adjusted. The adjustment board at the top of the neck of the instrument is desirably provided with integrally molded sleeves, in which are placed spring sleeves having extending necks. The necks are caused to extend between two studs which act as stops and prevent movement of the springs. These springs closely and tightly grip the pins by which the tension on the strings is adjusted and this is done without putting any particular strain upon the ukulele construction.

With the foregoing and other objects in view, the invention consists of the novel construction, combination and arrangement of parts as hereinafter more specifically described, and illustrated in the accompanying drawings, wherein is shown an embodiment of the invention, but it is to be understood that changes, variations and modifications can be resorted to which fall within the scope of the claims hereunto appended.

In the drawings wherein like reference characters denote corresponding parts throughout the several views:

Fig. l is a top plan view of a ukulele, made accord ing to the present invention, of a one-piece, molded back construction and a plurality of plates cemented thereto.

Fig. 2 is a vertical transverse longitudinal sectional view upon the line 2-2 of Fig. 1.

Fig. 3 is a fragmentary transverse vertical sectional view upon the line 3-3 of Fig. 1, upon an enlarged scale as compared to Fig. 1, showing the box and bridge construction.

Fig. 4 is a transverse vertical sectional view upon the line 4-4 of Fig. 1, upon an enlarged scale as compared to Fig. 1, showing the neck construction.

Fig. 5 is a transverse vertical sectional view upon the line 5-5 of Fig. 1, upon an enlarged scale as compared to Fig. 1, showing a tensioning board construction.

Fig. 6 is a fragmentary horizontal sectional view upon the line 6-6 of Fig. 2, showing the details of the tensioning arrangement upon an enlarged scale as cornpared to Fig. 2.

Fig. 7 is a fragmentary transverse vertical sectional view upon the line 7-7 of Fig. 6.

Fig. 8 is an inside or bottom plan view of the box cover shown in top View in Fig. 1 and upon a smaller scale than Fig. l.

Fig. 9 is a bottom or inside plan view of the cover element for the neck, shown in top view in Fig. 1, upon a smaller scale than Fig. 1.

Fig. 10 is a separated or exploded view of the molded plastic parts making up the ukulele of Figs. 1 and 2, showing them before they are assembled.

Referring to Figs. 1 to 10, there is shown a one-piece, molded back member A, having the shell-like sound box B, the shell-like neck C and the tensioning board D.

The cover elements consist of a molded box cover E, a molded neck cover F and a molded tensioning and adjustment board cover G.

Attached to the box cover E is the bridge H. The strings I extend from the bridge H to the tensioning and adjusting pin K, which are mounted in a tensioning and retaining arrangement L.

Referring particularly to the one-piece shell back structure as shown in Fig. 10 by itself and in Figs. 1, 2 and 3 in assembly, there is a main base 10 having the incurved side walls 11, the base wall 12 and the top wall 13.

The bridge member C is integrally molded with the box B and it has a curved base 14 with the relatively thick, upwardly and outwardly curved side walls 15. Adjacent the base it extends downwardly or rearwardly, as indicated at 16, and terminates in a flat section 17 which is slightly above the base 10 of the box B.

The neck C is separated from the top shell D by the transverse pin 18.

The shell of the adjusting board has side walls 19 which terminate at 22 below the upper edge of the supporting wall 18. It has a base wall 20 which is reinforced by the ribs 21 (see Figs. 2 and 16). It terminates in the curved end wall 23.

The upper edges 24 and 25 of the shell members B and D terminate without grooving. However, the upper edge 26 (see Fig. 4) of the neck member C is provided with a groove 27 (see particularly Fig. 4).

In respect to the cover member E, this member consists of a fiat plate 35 of molded plastic, with a central, reinforced opening 36 having the reinforcing ridges 37 above and below the opening. The plate has two transverse ridges 38 and 39 adjacent the positioning of the .ward projection 41 together with the projecting edge 42 will form a receptacle intosvhich the upper edge 24 may fit and be cemented into position.

The plate E -is also provided with the openings 44, which receive location pins through the bridge H.

V The bridge H consists of a box 45 having the ridge 46 over which the strings pass and the slots 47 in the top face 48 thereof.

The bottom face 49 has enlarged recesses 50, one for each slot, to enable a knot or holder for the strings I to be fitted into the slot 47.

The bottom edges of the box 45 are cemented to the top face ofthe plate Resting on topof the upper portion of the plate E at 60 is the extension 61 of the plate F covering'the shell neckC. This cover is of relatively heavy material as compared to the thickness 'of'the plate E or the shells B, C, and D and it has a series of ridges or frets 62 of increasing spacing toward the upper portion of the plate F.

The plate F terminates in the cross ridge 63 having recesses 64 to receive the strings.

The rear face of the plate F, as shown in Fig. 9, has the downwardly depending fins or ridges 66, which are spaced inside of the outer edges 67 and fit and are cemented into the recesses 27 on the back shell.

The top plate G for the tensioning board, as is shown in small scale in Figs. 1, 2 and 10'and larger scale in Figs. 5, 6 and 7, has a main top plate 75 from which project downwardly and inwardly integrally molded sleeves 76, which abut the base 200i the shell D at 77, as indicated in Figs. and 7.

Inside of the edge 78 are the downwardly projecting fins 79. These fins 79 extend around the upper side portions 80 and the upper edge portion '81 of the plate G (see Fig. and terminate above the lower edge 82.

The sleeves 76 correspond to the openings 83 in the top of the plate G. These sleeves G receive'the superimposed, circular leaf springs 84 and 85, which have tails 86. The tails 86 extend between and are heldor turned by the knobs or bosses 87 molded integrally with the plate G.

The adjusting members K have thepin shanks 95 which fit'through the circular springs'84 and 85 and then pass through the sleeves 96, which have mushrooms 97- abutting the outside face of the plate G. The sleeves 96 hold 'the circular springs 84 and 85 in position.

in a suitable holder. The-bridge'H is then cemented to the plate E and the plate E in turn is cemented to the sound box B.

Then the plate G is assembled with the round springs and 86 and is cemented to the box shell D.

Finally, the neck cover F is cemented in position.

The pins together with the outside guide sleeves 96 and mushrooms 97 are then assembled upon the tensioning board DG. The ends of the strings may be tied in the openings 99 of the pins 95' after they have been forced through the springs-8.4 and 85. The other ends of the strings I are locked into the slots 47 of the bridge H.

The ukelele, as shown, may be played just as an ordinaryukulele of wood and it has a high quality tone and yet is durable and Will withstand considerable handling.

While there has been herein described a preferred form of the invention, it should be understood that the same may be altered in details and in relative arrangement of parts within the scope of the appended claims.

Having now particularly described and ascertained the nature of the invention, and in what manner the same is to be performed, what is claimed is:

'-1. in a musical instrument construction, a musical instrument head, comprising a pair of spaced head portions adhered to each other, one of said head portions having integral hollow bosses abutted and adhered to the other of said head portions, metal bushings extending through said hollow bosses, and keys revolubly mounted in saidbushings, said bosses and metal bushings being split and said metal bushings having tail portions extending through the split sides of said bosses.

2. The construction of claim 1, one of said head portions also having a pair .of projecting studs 'integ-ra'lly' molded therewith and said tail portions projecting between and being stopped by said studs.

3. In a plastic ukelele construction, a tensioning arrangement having in separated spaced parallel relationship a molded head and cover, said head having an upstanding peripheral flange and said cover having a peripheral locating ridge fitting inside of said flange, said cover having downwardly projecting split sleeve bearings integrally molded therewith and also pairs of retaining knobs projecting downwardly from the cover adjacent the split sides of said sleeves and a plurality of cylindrical spring sleeves positioned in said bearings with projecting tails held between said pairs of knobs.

References Cited in the file of this patent UNITED STATES PATENTS Re. 23, 620 Finder Feb. 24, 1953 629,374 Kindig July 25, 1899 711,396 Gregg Oct. 14, 1902 1,548,777 Coughi Aug. 4, 1925 1,881,229 Young Oct. .4, 1932 2,029,135 Stanley et al. Jan. 28, 1936 2,186,424 Moertel Jan. 9, 1940 2,583,478 Finder Jan. 21, 1952 2,588,101 Finder Mar. :4, 1952 2,597,154 Maccaferri May 20, 1952 2,614,448 Maccaferri Oct. 21, 1952 

